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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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25
26/* @test
27 * @bug 8139885
28 * @bug 8143798
29 * @run testng/othervm -ea -esa test.java.lang.invoke.SpreadCollectTest
30 */
31
32package test.java.lang.invoke;
33
34import java.io.StringWriter;
35import java.lang.invoke.MethodHandle;
36import java.lang.invoke.MethodHandles;
37import java.lang.invoke.MethodHandles.Lookup;
38import java.lang.invoke.MethodType;
39import java.lang.invoke.WrongMethodTypeException;
40import java.util.*;
41
42import static java.lang.invoke.MethodType.methodType;
43
44import static org.testng.AssertJUnit.*;
45
46import org.testng.annotations.*;
47
48/**
49 * Tests for the new asSpreader/asCollector API added in JEP 274.
50 */
51public class SpreadCollectTest {
52
53    static final Lookup LOOKUP = MethodHandles.lookup();
54
55    @Test
56    public static void testAsSpreader() throws Throwable {
57        MethodHandle spreader = SpreadCollect.MH_forSpreading.asSpreader(1, int[].class, 3);
58        assertEquals(SpreadCollect.MT_spreader, spreader.type());
59        assertEquals("A456B", (String) spreader.invoke("A", new int[]{4, 5, 6}, "B"));
60    }
61
62    @Test
63    public static void testAsSpreaderExample() throws Throwable {
64        // test the JavaDoc asSpreader-with-pos example
65        MethodHandle compare = LOOKUP.findStatic(Objects.class, "compare", methodType(int.class, Object.class, Object.class, Comparator.class));
66        MethodHandle compare2FromArray = compare.asSpreader(0, Object[].class, 2);
67        Object[] ints = new Object[]{3, 9, 7, 7};
68        Comparator<Integer> cmp = (a, b) -> a - b;
69        assertTrue((int) compare2FromArray.invoke(Arrays.copyOfRange(ints, 0, 2), cmp) < 0);
70        assertTrue((int) compare2FromArray.invoke(Arrays.copyOfRange(ints, 1, 3), cmp) > 0);
71        assertTrue((int) compare2FromArray.invoke(Arrays.copyOfRange(ints, 2, 4), cmp) == 0);
72    }
73
74    @DataProvider
75    static Object[][] asSpreaderIllegalPositions() {
76        return new Object[][]{{-7}, {3}, {19}};
77    }
78
79    @Test(dataProvider = "asSpreaderIllegalPositions")
80    public static void testAsSpreaderIllegalPos(int p) throws Throwable {
81        boolean caught = false;
82        try {
83            SpreadCollect.MH_forSpreading.asSpreader(p, Object[].class, 3);
84        } catch (IllegalArgumentException iae) {
85            assertEquals("bad spread position", iae.getMessage());
86            caught = true;
87        }
88        assertTrue(caught);
89    }
90
91    @Test(expectedExceptions = {WrongMethodTypeException.class})
92    public static void testAsSpreaderIllegalMethodType() {
93        MethodHandle h = MethodHandles.dropArguments(MethodHandles.constant(String.class, ""), 0, int.class, int.class);
94        MethodHandle s = h.asSpreader(String[].class, 1);
95    }
96
97    @Test
98    public static void testAsCollector() throws Throwable {
99        MethodHandle collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 1);
100        assertEquals(SpreadCollect.MT_collector1, collector.type());
101        assertEquals("A4B", (String) collector.invoke("A", 4, "B"));
102        collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 2);
103        assertEquals(SpreadCollect.MT_collector2, collector.type());
104        assertEquals("A45B", (String) collector.invoke("A", 4, 5, "B"));
105        collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 3);
106        assertEquals(SpreadCollect.MT_collector3, collector.type());
107        assertEquals("A456B", (String) collector.invoke("A", 4, 5, 6, "B"));
108    }
109
110    @Test
111    public static void testAsCollectorInvokeWithArguments() throws Throwable {
112        MethodHandle collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 1);
113        assertEquals(SpreadCollect.MT_collector1, collector.type());
114        assertEquals("A4B", (String) collector.invokeWithArguments("A", 4, "B"));
115        collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 2);
116        assertEquals(SpreadCollect.MT_collector2, collector.type());
117        assertEquals("A45B", (String) collector.invokeWithArguments("A", 4, 5, "B"));
118        collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 3);
119        assertEquals(SpreadCollect.MT_collector3, collector.type());
120        assertEquals("A456B", (String) collector.invokeWithArguments("A", 4, 5, 6, "B"));
121    }
122
123    @Test
124    public static void testAsCollectorLeading() throws Throwable {
125        MethodHandle collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 1);
126        assertEquals(SpreadCollect.MT_collectorLeading1, collector.type());
127        assertEquals("7Q", (String) collector.invoke(7, "Q"));
128        collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 2);
129        assertEquals(SpreadCollect.MT_collectorLeading2, collector.type());
130        assertEquals("78Q", (String) collector.invoke(7, 8, "Q"));
131        collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 3);
132        assertEquals(SpreadCollect.MT_collectorLeading3, collector.type());
133        assertEquals("789Q", (String) collector.invoke(7, 8, 9, "Q"));
134    }
135
136    @Test
137    public static void testAsCollectorLeadingInvokeWithArguments() throws Throwable {
138        MethodHandle collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 1);
139        assertEquals(SpreadCollect.MT_collectorLeading1, collector.type());
140        assertEquals("7Q", (String) collector.invokeWithArguments(7, "Q"));
141        collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 2);
142        assertEquals(SpreadCollect.MT_collectorLeading2, collector.type());
143        assertEquals("78Q", (String) collector.invokeWithArguments(7, 8, "Q"));
144        collector = SpreadCollect.MH_forCollectingLeading.asCollector(0, int[].class, 3);
145        assertEquals(SpreadCollect.MT_collectorLeading3, collector.type());
146        assertEquals("789Q", (String) collector.invokeWithArguments(7, 8, 9, "Q"));
147    }
148
149    @Test
150    public static void testAsCollectorNone() throws Throwable {
151        MethodHandle collector = SpreadCollect.MH_forCollecting.asCollector(1, int[].class, 0);
152        assertEquals(SpreadCollect.MT_collector0, collector.type());
153        assertEquals("AB", (String) collector.invoke("A", "B"));
154    }
155
156    @DataProvider
157    static Object[][] asCollectorIllegalPositions() {
158        return new Object[][]{{-1}, {17}};
159    }
160
161    @Test(dataProvider = "asCollectorIllegalPositions")
162    public static void testAsCollectorIllegalPos(int p) {
163        boolean caught = false;
164        try {
165            SpreadCollect.MH_forCollecting.asCollector(p, int[].class, 0);
166        } catch (IllegalArgumentException iae) {
167            assertEquals("bad collect position", iae.getMessage());
168            caught = true;
169        }
170        assertTrue(caught);
171    }
172
173    @Test
174    public static void testAsCollectorExample() throws Throwable {
175        // test the JavaDoc asCollector-with-pos example
176        StringWriter swr = new StringWriter();
177        MethodHandle swWrite = LOOKUP.
178                findVirtual(StringWriter.class, "write", methodType(void.class, char[].class, int.class, int.class)).
179                bindTo(swr);
180        MethodHandle swWrite4 = swWrite.asCollector(0, char[].class, 4);
181        swWrite4.invoke('A', 'B', 'C', 'D', 1, 2);
182        assertEquals("BC", swr.toString());
183        swWrite4.invoke('P', 'Q', 'R', 'S', 0, 4);
184        assertEquals("BCPQRS", swr.toString());
185        swWrite4.invoke('W', 'X', 'Y', 'Z', 3, 1);
186        assertEquals("BCPQRSZ", swr.toString());
187    }
188
189    static class SpreadCollect {
190
191        static String forSpreading(String s1, int i1, int i2, int i3, String s2) {
192            return s1 + i1 + i2 + i3 + s2;
193        }
194
195        static String forCollecting(String s1, int[] is, String s2) {
196            StringBuilder sb = new StringBuilder(s1);
197            for (int i : is) {
198                sb.append(i);
199            }
200            return sb.append(s2).toString();
201        }
202
203        static String forCollectingLeading(int[] is, String s) {
204            return forCollecting("", is, s);
205        }
206
207        static final Class<SpreadCollect> SPREAD_COLLECT = SpreadCollect.class;
208
209        static final MethodType MT_forSpreading = methodType(String.class, String.class, int.class, int.class, int.class, String.class);
210        static final MethodType MT_forCollecting = methodType(String.class, String.class, int[].class, String.class);
211        static final MethodType MT_forCollectingLeading = methodType(String.class, int[].class, String.class);
212
213        static final MethodHandle MH_forSpreading;
214        static final MethodHandle MH_forCollecting;
215        static final MethodHandle MH_forCollectingLeading;
216
217        static final MethodType MT_spreader = methodType(String.class, String.class, int[].class, String.class);
218        static final MethodType MT_collector0 = methodType(String.class, String.class, String.class);
219        static final MethodType MT_collector1 = methodType(String.class, String.class, int.class, String.class);
220        static final MethodType MT_collector2 = methodType(String.class, String.class, int.class, int.class, String.class);
221        static final MethodType MT_collector3 = methodType(String.class, String.class, int.class, int.class, int.class, String.class);
222        static final MethodType MT_collectorLeading1 = methodType(String.class, int.class, String.class);
223        static final MethodType MT_collectorLeading2 = methodType(String.class, int.class, int.class, String.class);
224        static final MethodType MT_collectorLeading3 = methodType(String.class, int.class, int.class, int.class, String.class);
225
226        static final String NONE_ERROR = "zero array length in MethodHandle.asCollector";
227
228        static {
229            try {
230                MH_forSpreading = LOOKUP.findStatic(SPREAD_COLLECT, "forSpreading", MT_forSpreading);
231                MH_forCollecting = LOOKUP.findStatic(SPREAD_COLLECT, "forCollecting", MT_forCollecting);
232                MH_forCollectingLeading = LOOKUP.findStatic(SPREAD_COLLECT, "forCollectingLeading", MT_forCollectingLeading);
233            } catch (Exception e) {
234                throw new ExceptionInInitializerError(e);
235            }
236        }
237
238    }
239
240}
241